Original Research Article DOI: 10.18231/2394-4994.2017.0092 Indian Journal of Clinical Anaesthesia, 2017;4(4): 463-468 463 A study of the effect of caudal epidural neostigmine for post operative pain relief in children undergoing lower abdominal surgery Kannan Santhanakrishnan 1 , VS Senthil Kumar 2,* 1 Assistant Professor, Saveetha Medical College & Hospital, Thandalam, Chennai, 2 Associate Professor, Dept. of Anaesthesiology, IRT Perunthurai Medical College & Hospital, Erode District *Corresponding Author: Email: dr.vs.md@gmail.com Abstract Introduction and Objective: Providing adequate pain relief has always been part of anaesthesiologist’s role in the perioperative period beyond post anaesthesia care unit. Among the many adjuvants studied neostigmine was also found to be effective in acute post-operative and chronic pain. We have studied the analgesic efficacy of caudal bupivacaine with and without neostigmine in children. Materials and Method: In this randomized double blind study, sixty children belonging to ASA I and II, aged 2-8 years undergoing lower abdominal surgeries were randomly allocated into two groups to receive a caudal injection of 0.25% bupivacaine alone or a mixture of 0.25% bupivacaine 0.5ml/kg with 2μg/kg neostigmine. Monitoring of scores for pain, postoperative nausea and vomiting was performed by an Anaesthesiologist blinded to the study allocations. Results: Time to the first analgesic administration of syrup Paracetamol was longer (P<0.05) with mean duration of analgesia of 14.6 hrs in the bupivacaine-neostigmine than in the bupivacaine only group with a mean duration of 4.3 hrs. Side effect such as emesis was not significantly different between the two groups. Conclusion: Caudal co-administration of bupivacaine with neostigmine produces significant prolongation of the duration of postoperative analgesia when compared to caudal bupivacaine alone. Keywords: Bupivacaine, Caudal epidural, Neostigmine, Ramsay scale, Aldrete score Introduction Pain now has become the fifth vital sign and has become a critical focus of the patient management. Optimization of pain has a major role in improving the clinical outcome, felicitate early recovery, mobilization and return to daily living. Mismanaged pain relief can lead to physiologic complications, psychological distress, and personality changes in developing children, family disruption, interruption of hospital routine and prolongation of hospitalization with resultant increased costs. Many methods of reducing were used to avoid under treatment of pain in pediatric patients. Many adjuvants have been tried with bupivacaine like clonidine, morphine, and fentanyl etc. (1) Various methods have been tried to prolong the duration of regional analgesia with local Anaesthetic like placing a catheter and the use of an adjuvant. Caudal epidural block with bupivacaine is very effective until the immediate postoperative period. (10-11) Though accepted the presence of a catheter for postoperative pain relief has a potential risk of infection and the use of adjuvants like opioids, clonidine and ketamine has limitations due to the adverse effects such as Respiratory depression, sedation, nausea and vomiting. (21) There has been various studies of neostigmine as an adjuvant along the local anaesthetic epidurally and it’s been established as an analgesic in adults and children. Caudal neostigmine in a dosage of 2μg/kg with the local anaesthetic has been found to prolong analgesia. Neostigmine acts by inhibiting the breakdown of acetylcholine the endogenous neurotransmitter thereby producing analgesia when given with a central neuraxial route. (1) It has been theorized that the analgesic effect is mediated through spinal muscarinic receptors. In the pediatric patients a dose response study of caudal neostigmine has proved to be safe and effective (7) and also it has been observed that with neostigmine in the range of 20-50ug/kg a dose dependent analgesia is produced. In children undergoing genitourinary surgery caudal neostigmine 2ug/kg with bupivacaine 0.25% has an extended duration of post-operative analgesia up to 20 hrs, and thereby reduces the need for additional analgesics. Aim To study the effect of neostigmine on the duration of caudal block produced by 0.25% bupivacaine in a volume of 0.5ml/kg in children undergoing lower abdominal surgery. Materials and Method After the institutional ethical committee approval 60 children belonging to ASA I and II in the age group of 2 years to 8 years scheduled to undergo elective lower abdominal surgery at Raja Mirasudhar Hospital, Tanjavur Medical College between January and August 2007 were chosen for this study. Children with local sepsis, bleeding diathesis, cardio respiratory diseases, preexisting neurological or spinal diseases and congenital anomaly of back were excluded. The parents were informed about the procedure and a written consent was obtained for postoperative